非均匀杂波背景下双基地MIMO雷达距离扩展目标的GLRT检测

利用球不变随机矢量(Spherically Invariant Random Vector, SIRV)描述非均匀杂波, 建立了双基地多输入多输出(Multiple-Input Multiple-Qutput, MIMO)雷达距离扩展目标的信号检测模型, 提出了距离扩展目标的两步广义似然比检测(Generalized Likelihood Ratio Test, GLRT)算法.首先, 根据目标散射系数的两种假设模型, 分别推导确定型目标、高斯型目标GLRT检测器的解析表达式, 然后利用固定点迭代算法估计杂波协方差矩阵, 获得自适应GLRT(AD-GLRT和AG-GLRT)检测器.仿真实验表明:AD-GLRT和AG-GLRT检测器的检测性能均优于非均匀杂波背景、高斯杂波背景下点目标的检测性能, 且两者的检测性能相当, 并且虚拟阵元数、目标分布的距离单元数, 以及信杂比越大, 两者的检测性能越好.

GLRT-based detection algorithm for range-spread targets of bistatic MIMO radar in nonhomogenous clutter

The signal detection model of range-spread target of bistatic multiple-input multiple-output(MIMO) radar is formulated by using the spherically invariant random vectors(SIRV) to describe the non-homogenous clutter. A two-step generalized likelihood ratio test(GLRT) detector algorithm is proposed for detecting the range-spread target. Two different assumptions are made concerning the radar cross section(RCS) coefficient of target: either modeled as deterministic unknown or as Gaussian parameter. Then the GLRT detectors for range-spread target are derived under these two hypotheses. It shows that both detectors lead to the similar results for range-spread target, and the proposed detector enables a detection performance enhancement over that of the point target detectors in the both non-homogenous and Gaussian clutters. Furthermore, the detection performance of both the proposed detectors increases as the virtual aperture number, the target range cell number and the Signal Clutter Ratio (SCR) increase.